Carbon dioxide is a well-known gas, which is present in the atmosphere. It is released to the atmosphere in large amounts by fermentation processes, limestone calcination, and all forms of combustion processes of carbon and carbon compounds. In the recent decades, the attention in respect of said emission has been rising, because of the environmental problem due to future climate change via Greenhouse effect. Consequently, extensive work has been performed over the years in order to develop processes for the removal of carbon dioxide from combustion gases. If possible, a subsequent recovery of carbon dioxide may make those processes economical feasible.
Various methods for removal of a gaseous component from a gas stream are known in the art. Especially, absorption followed by stripping with various modifications has been mentioned as suitable methods for removal of components from gaseous waste streams.
It is well known that even marginal optimizations in large-scale carbon dioxide recovery facilities may result in a substantial increase in yield and/or reduction in production costs. There are numerous ways to optimize the process in order to achieve a reduction of energy consumption of the overall process, thus achieving a large economical saving. In large-scale production facilities the thermal energy of combustion gases are often not fully utilized, and is thus wasted. Optimising the utilization of this thermal energy is one way of reducing the overall energy consumption of the facilities.
The object of the present invention is to provide a more economical method for recovery of carbon dioxide from a CO2-containing gas.